During my current work on Y chromosome markers I frequently ran into the question where exactly those markers are located. The location of the markers is often the key to understand the recombination mechanisms and if multiple markers are aligned to the same reference sequence we find out that markers with different names may in fact be one and the same location on the Y chromosome.

Looking up marker positions in public databases has been time consuming and needs a lot of knowledge in molecular biology. For this reason I have collected information about all kind of Y chromosome markers and their positions along the current HUGO reference sequence. To make this all accessible to the public I have arranged the data in a HapMap style genome browser and we have setup a webserver at Family Tree DNA so that it can be accessed at a high speed internet connection.

Just type in a marker name into the Landmark or Region field and submit the Search. Examples: M201, DYS456, or a region like Yq11.221

The browser will show the position of the marker in the Overview graphic and it will zoom at the propitiate range in the Details view. If you zoom out a little bit, you will see the markers in the neighboring region. The marker of interest will be highlighted in yellow so that you don't loose its position. If you click on the marker it will display more detailed information and sometimes a link to more external resources like NCBI or GDB. The numbering of the reference DNA sequence is exactly synchronized with other ressources like the UCSC genome browser (Human March 2006 http://genome.ucsc.edu/)

The Y chromosome browser is still under development, so essential features and markers are still missing, but I thought that it is already very helpful for the advanced DNA genealogist and I didn't want you to wait much longer before you can try it. The database already contains more than 40.000 features and it will be updated frequently. I believe that some specialist genealogists out there may find errors and missing features. We intend to make the browser as complete as possible, so please send all requests to my e-mail address: thomas@familytreedna.com . Thanks for your help and have fun exploring the Y chromosome!